Improvement in chuck



waited giedre parte can.

Letters Patent No. 94,376, dated August 31, 1869.

IMPROVEMENT IN CHUCK.

The Schedule referred to in these Letters Patent and making part of thegame.

To all who-m it may concern.-

Be it known that I, W. F. Bacon, of Skowhegain in the county' ofSomerset, andState of Maine, have invented a new and valuableImprovement in Portable Chuck-Jaws; and I do hereby declare thatthe'following is a full, clear, and exact description of theconstruction and operation yof the same, reference being had to theannexed drawings, making a part of this specification, and to theletters and figures of reference marked thereon.

Figure 1, ofthe drawings, is a vertical longitudinal section through thecentre of my chuck-jaw.

, Figure 2 is a top view of -the chuck-jaw.

Figure 3 is a vertical cross-section through Vthe centre ofthe bolt, inthe line x x.

My invention relates to an improvement in chuckjaws, attached to theface-plates of engine or shaftinglathes; and consists, mainly, in anovel arrangement of devices, whereby the chuck-jaw may be easily andsecurely set up to the work, and `firmly bolted to the face-plate.

The letter A, of the drawings, designates the bedpiece of the chuck-jaw,which is, in form, a parallelopiped, having a slot in its front surface,and formed on its rear surface a rib, B, and bolt G.

The rib B fits in the slot of the face-plate, through which the bolt Opasses, on the endof which is screwed the nut vF, thereby rinly securingthe chuck-jaw to the face-plate in any desired posit-ion, with referenceto the slot of the face-plate.

I) represents the sliding jaw, having a stud or projection, d', formedon its rear side, which slides in the slot in the front surface of thebed-piece A. Out in this projection is a female screw, workin gon ascrew, E.

The front portion of the sliding jaw is formed into steps, in order thatit may be with greaterv facility ladble end-piece a, which, after thescrew is placed in po-l. sition, is secured to the body of the bed-pieceby the screws a a'.

The other end of the screw E 1s expanded, forming a collar, e', fittingin a depression in the end of the slotv in the bed-piece, and thencontracted, forming a journal, which passes entirely through a bearingin the end of the bed-piece, and finally fashioned into a square head,whereby the screw E -is turned, a key being applied thereto.

lo confine the jaws to the bed-piece, the front surface of the bed-pieceA may have formed ou it parallel bars m Im., grooved in their innersurfaces, to receive vtongues a n', formed on the sides of the base ofthe sliding jaw D; but thisV I do not regard so good a method as thatshown in Figure 4.

I do not desire to confine myself to the form ofthe slot in bed-pieceA,as in g. 4, but sometimes prefer to form the grooves with tongues, asshown invg. 3.

What I claim as my invention, and desire to secure by Letters Patent,is-

The adjustable bed-piece A, rib B, bolt G, with nut F and washer G, .thescrew E, sliding jaw D, substantially as shown and described.

In testimony that I claim the above, I have hereunto subscribed my name,in the presence of two witnesses.

Witnesses: W. F. BACON.

HIRAM KNOWLTON, Lnvr YOUNG.

